I have been following the threads related to the best bang for the buck upgrades for awhile. I agree with the many who believe that for a daily driver looking for a little more power a 6.0 pullout is the way to go.

SO my question is... What changes are required to raise the power of the LQ4 to somewhere near the LQ9?

From what I have read the LQ9 is nearly identical except for the 10.0 CR. If this is true a mild valve porting, head shave and a thinner gasket should get you there on the cheap without having to crack the bottom of the motor.

What if any clearance issues (V/P, P/H, quench) would this raise?
Are thinner gaskets available?

Newbie

 

It would tighten all those clearances you mentioned. You'd gain CR and have a nice tight quench. Felpro makes a thinner head gasket - 1041. It has a compressed height of .043 compared to the stock .060 and is a 4.1 bore.

 

So the 0.017 thinner gasket gets you to 9.6-9.7 CR range. Is there enough room to thin the head to get to 10 or so? or will there be clearance issures?

What else would have to be done to get to the 345hp, 380 ft-lb of torque of the LQ9? Would the bottom end of the motor require any changes? Remember the end goal is something in the LQ9 range (or higher) on the (really) cheap.

Thanks